Mass-radius relation for accreted and catalyzed NSs for the EoSs based on the BSk19, BSk20, and BSk21 EDFs. Results obtained from Eq. (13) are indistinguishable from the exact ones. The coloured areas represent the recent mass-radius measurements (at 1σ) from NICER of PSR J0030+0451 and PSR J0740+6620. The analyses of Riley et al. (2019, 2021) are shown in green and those of Miller et al. (2019, 2021) in blue. See text for details.